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31.
A N Phillips J D Neaton D G Cook R H Grimm A G Shaper 《American journal of epidemiology》1992,136(1):59-70
The association between leukocyte count and subsequent risk of major coronary heart disease events was examined using data from three prospective cohort studies--two from the United States and one from Great Britain. A total of 28,181 middle-aged men were followed for 6-12 years. A total of 1,768 men had a nonfatal myocardial infarction or died of coronary heart disease. In all three cohorts, there was a positive, statistically significant relation between baseline leukocyte count and risk of subsequent major coronary heart disease events after adjustment for age, serum total cholesterol, diastolic blood pressure, and number of cigarettes smoked per day (relative odds = 1.32 (p less than 0.0001), 1.15 (p = 0.0001), and 1.14 (p = 0.003), corresponding to a 2,000/mm3 difference in leukocyte count). The associations persisted when all nonsmokers (former smokers plus never smokers) and never smokers alone were considered and when those with evidence of preexisting coronary heart disease at baseline were excluded. Leukocyte count appears to be an indicator of a person's future risk of major coronary heart disease events. 相似文献
32.
Changes in temporal gait characteristics and pressure distribution for bare feet versus various heel heights 总被引:8,自引:0,他引:8
The purpose of this study was to identify changes in temporal gait characteristics and pressure generation across the sole of the foot due to various heel heights in women's dress pumps. Thirty female subjects, aged 18-30 years, volunteered to participate. Subjects were required to have normal gait and to wear comfortably either size 7 or size 9 shoes. Subjects were tested initially in bare feet using electrodynography (Langer Biomechanics Group, 21 East Industry Court, Deer Park, NY 11729-9986) (EDG) at a cadence of ~100 steps/min set by metronome. EDG trials with 4 pairs of shoes were then performed in random order. Shoes were women's dress pumps identical except for heel height. Heel heights were 1.75, 3.12, 5.72 and 8.74 cm. Data were collected over ~ 30 steps and averaged over this period. Data were analyzed using a one-way ANOVA, and changes were only considered significant if the ANOVA identified significant variations bilaterally. Considering temporal gait variables, we concluded that: (1) stance phase was shortened in shoes vs. bare feet but was unaffected by heel height, (2) the percentage of stance spent in weight bearing on the lateral and medial calcaneus decreased above a 3.12 cm heel height, (3) the percentage of stance spent in weight bearing on the first and second metatarsal heads increased in shoes vs. bare feet but was unaffected by heel height, (4) the percentage of stance spent in weight bearing on the fifth metatarsal was less in the 8.74 cm heel than in any other shoe or in bare feet. With regard to pressure variables, we found that: (1) peak pressure under the fifth metatarsal head was inversely related to heel height, (2) pressure under the third metatarsal head peaked earliest in heels greater than 5.72 cm high, and (3) pressure under the medial calcaneus peaked latest in heels greater than 5.72 cm high. 相似文献
33.
Using a simplified procedure, we have extracted DNA from unstained paraffin sections of needle biopsies of kidney and liver transplants and identified the presence of CMV using the polymerase chain reaction. This method utilizes oligonucleotide primers for two genes shown to be specific for cytomegalovirus (CMV) as well as an internal control gene (hemoglobin) in a single reaction. Utilizing nested PCR amplification with agarose gel electrophoresis, CMV can be detected without radioisotopes to a level of sensitivity equivalent to one one-hundredth of a cytomegalic virocyte per cm2 of a 3-microM paraffin section. This method is applicable to situations where only scarce paraffin-embedded tissue is available. 相似文献
34.
Health effects of passive smoking. 1. Parental smoking and lower respiratory illness in infancy and early childhood 总被引:15,自引:9,他引:6 下载免费PDF全文
BACKGROUND: A systematic quantitative review was conducted of evidence relating parental smoking to acute lower respiratory illness in the first three years of life. METHODS: Fifty relevant publications were identified after consideration of 692 articles selected by electronic search of the Embase and Medline databases using keywords relevant to passive smoking in children. The search, completed in April 1997, identified 24 studies ascertaining illnesses in a community setting, including five surveys of schoolchildren with retrospective ascertainment of early chest illness, and 17 studies of admissions to hospital for lower respiratory illness in early life. Thirty eight studies were included in a quantitative overview using random effects modelling to derive pooled odds ratios. RESULTS: The results of community and hospital studies are broadly consistent, with only one publication reporting a reduced risk among children of smokers. The pooled odds ratios were 1.57 (95% CI 1.42 to 1.74) for smoking by either parent and 1.72 (95% CI 1.55 to 1.91) for maternal smoking. There is a significantly increased risk of early chest illness associated with smoking by other household members in families where the mother does not smoke (1.29, 95% CI 1.16 to 1.44). The associations with parental smoking are robust to adjustment for confounding factors, and show evidence of a dose-response relationship in most studies in which this has been investigated. CONCLUSIONS: The relationship between parental smoking and acute lower respiratory illness in infancy is very likely to be causal. Although it is impossible to distinguish the independent contributions of prenatal and postnatal maternal smoking, the increased risk associated with smoking by other household members suggests that exposure to environmental tobacco smoke after birth is a cause of acute chest illness in young children.
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35.
Passive smoking and sudden infant death syndrome: review of the epidemiological evidence 总被引:5,自引:1,他引:4 下载免费PDF全文
BACKGROUND: This paper provides a systematic, quantitative review of the epidemiological evidence relating parental smoking and sudden infant death. METHODS: Thirty two relevant publications were identified after consideration of 692 articles selected by electronic search of the Embase and Medline databases using keywords and Mesh headings relevant to passive smoking in children. Eleven further articles were identified from reviews and by talking to authors. The search was completed in April 1997 and identified 39 studies. RESULTS: The unadjusted pooled odds ratio for prenatal maternal smoking was 2.77 (95% CI 2.45 to 3.13). After adjustment for a variety of confounders the pooled odds ratio was reduced to 2.08 (95% CI 1.83 to 2.38) and was similar in cohort and case-control studies. Four studies reported on maternal postnatal smoking after controlling for prenatal maternal smoking (pooled odds ratio 1.94 (95% CI 1.55 to 2.43)). Of three studies reporting on the risk of paternal smoking where the mother was a non-smoker, two found significant effects while one found no effect. Dose-response relationships with both prenatal and postnatal maternal smoking were present in most studies which provided data. CONCLUSIONS: Maternal smoking doubles the risk of sudden infant death syndrome. The relationship is almost certainly causal. There is good evidence that postnatal exposure to environmental tobacco smoke from both mother and father are important. Because prenatal smoking is almost invariably associated with postnatal smoking, the role of prenatal smoking per se will be difficult to resolve using epidemiological studies.
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36.
Robert T. Cook Thomas J. Waldschmidt Zuhair K. Ballas Brian L. Cook Brenda M. Booth Barbara C. Stewart Michael J. Garvey 《Alcoholism, clinical and experimental research》1994,18(1):71-80
Alcoholics admitted to the hospital solely for detoxication have been studied by flow cytometry to evaluate changes in the surface markers of peripheral blood leukocytes. As we have shown previously, such patients have an elevated percentage of CD8hl lymphocytes that are HLA DR+; we now demonstrate that they also have striking alterations in the quantitative relationships of the fine T-cell subsets. Both CD4+ and CD8hl lymphocytes have a sharply reduced percentage of the l -selectin+ CD45RA+ subset, increased percentages of the CD45RA-subsets, and several other fine subset alterations. The fine subset profile suggests, according to current correlations of phenotype and function, that both CD4+ suppressor inducer and CD4-dependent CD8+ suppressor effector cells are reduced, whereas other subsets, including CD8+ CTL or their precursors, are increased in relative percentages. Some of the phenotypic changes are reversible over the several days following withdrawal. In other results, the percentage of CD8hl lymphocytes expressing CD11b (β-integrin) is shown to be reciprocal with the percentage expressing l -selectin both in normals and alcoholics. However, the regression function of CD11b vs. l -selectin on CD8hl cells is different for the alcoholics than for the normals, indicating an abnormality in the regulation of the expression of these two adhesion markers. Taken together, this abnormality of adhesion molecules and the fine subset alterations previously described indicate widespread changes in the peripheral lymphocytes of currently drinking alcoholics. These changes suggest functional deficiencies that may include alterations of lymphocyte traffic and other adhesion-dependent functions, and a shift in the balance of regulatory interactions. 相似文献
37.
38.
Job ending among youth and adults with severe mental illness 总被引:1,自引:0,他引:1
This study examined job leaving over a 36-month period among 326 persons (74 youth and 252 adults) with severe mental illness who were participating in an urban vocational rehabilitation program. Data from 627 job endings indicated that younger clients displayed job-ending patterns that were different in some aspects from such patterns for nondisabled youth (such as displaying a lower average job tenure) yet similar to job-ending patterns for nonhandicapped youth in other ways (such as displaying a high frequency of job changing). Youth and their adult counterparts with mental illness displayed similar tenure on agency-sponsored placements but significantly different tenure on independent jobs. While adults held their independent jobs for an average of seven months, youth averaged only three months at competitive employment. Youth also were significantly more likely than adults to be fired from both placements and independent jobs. These findings and others are discussed in terms of their implications for development of public policy and service delivery models for providing on-going job support to youth and adults with severe psychiatric disabilities. 相似文献
39.
Aaron R. Folsom Timothy C. Cook J. Michael Sprafka Gregory L. Burke Stephan W. Norsted David R. Jacobs Jr. 《Journal of behavioral medicine》1991,14(1):1-9
Energy expenditure in leisure-time physical activity (LTPA) was measured using the Minnesota LTPA Questionnaire in 35- to 74-year-old black and white residents of Minneapolis-St. Paul, Minnesota. Estimates of the geometric mean LTPA energy expenditure were 129 and 204 kcal per day for black and white men (p<.05) and 91 and 123 kcal per day for black and white women (p<.05). The percentage of individuals expending 2000 kcal or more per week in LTPA was significantly lower in black men than white men (25 vs. 35%; p=.01) but was not different in black versus white women (18 vs. 17%). Although black men and women reported greater occupational physical activity than their white counterparts, LTPA and job activity were unrelated in all race and sex groups. In both races, LTPA energy expenditure declined with age. LTPA increased with level of formal education, and the largest LTPA difference between blacks and whites was observed in those who had a high-school diploma or less. Blacks had lower participation rates than whites in most of the individually assessed physical activities. Additional research is needed on the determinants and promoters of LTPA in population subgroups.The research was funded by National Heart, Lung, and Blood Institute Research Grant R01 HL 23727 and National Research Award T32 HL 07328-10. 相似文献
40.
Bilateral transpedicular decompression and Harrington rod stabilization in the management of severe thoracolumbar burst fractures. 总被引:2,自引:0,他引:2
Fifty-eight patients with severe thoracolumbar burst fractures were treated with bilateral transpedicular decompression, Harrington rod instrumentation, and spine fusion. Spinal realignment and stabilization was achieved by contoured dual Harrington distraction rods supplemented by segmental sublaminal wiring. Posterior element fractures were noted in 25 patients, 9 of whom had associated dural tears. Computed tomography was performed to assess the cross-sectional area of the spinal canal before surgery and after decompression. Patients at initial evaluation averaged greater than 67% spinal canal compromise. After surgery, successful decompression was accomplished in 57 patients. One patient required staged, anterior thoracoabdominal decompression and fibula strut grafting. At follow-up (average, 43 months; range, 25-70 months), neurologic improvement was found in 77% of the patients who initially presented with neurologic deficits. Thirty-four of 40 patients with incomplete paraplegia improved one or more subgroups on the Frankel scale. A solid fusion was attained in all 58 patients. No patient had a significant residual kyphotic deformity. Single-stage bilateral transpedicular decompression and dual Harrington rod instrumentation reliably provides decompression of the spinal canal and restores spinal alignment. The procedure allows early mobilization and provides an environment for solid fusion and maximum neurologic return. 相似文献